as simon perez shouse us the criteria for that list. simon. >> reporter: dana there appears to be some debate about whether that list was a secret but we can tell you right now you can find out for yourself. >> whenever we identify any potential threat to public safety we immediately go and address the situation. we don't put it on solis, it's not on solis of 100. >> reporter: but for planning purposes pg&e does make up a list of the 100 most dangerous pipeline segments so it nose which ones to fix before others. these maps posted on the company's web site show where they are. they get there based on criteria. will there or has there been third party construction nearby that could affect the pipe, pipe corrosion, land movement near the pipe such as, and the pipe's age, design, and what its made of. >> this list is in flux. some items will move up the list, some items will move down the list. >> reporter: they also included broader maps to show the entire pipeline system so customers can find out if they live near a pipe, risky or not. w